Watchdog Hardware Access - Kontron MSM-LP User Manual

4.4.2 Watchdog Hardware Access

The watchdog registers of the F81216 chip are accessible over I/O mapped registers with indexed access. The
following table shows the addresses used. The F81216 chip has few devices and the watchdog is device number 8.
Address Name
0x4E IND
0x4F DAT
Indexed Register Map of Watchdog Device 08h
Index Bit Name
0x30 0 WDT_EN
0x30 1-7
0xF0 0 WDT_EVENT
0xF0 1-2 WDT_UNIT
0xF0 3-7
0xF1 7-0 WDT_CNT
Register Attributes
Attribute Description
RsvdP RESERVED AND PRESERVED
Reserved for future RW implementations. Registers are Read-only and the software must preserve the value for
writes to this bit.
RW READ-WRITE REGISTER
Register bits are Read-Write and can be set or cleared by software.
RO READ-ONLY
Register bits are Read-only and can not be altered by software.
WO WRITE-ONLY
Register bits can only be Written. Reading returns indeterminable data.
28
Type Description
RW Indexed register access number
RW Indexed register content
Access Function
RW Watchdog device enable register: 0=disable,1=enable
RsvdP Reserved
0: no time out has occurred
RO
1: time out has occurred
Writing "1" to this bit will clear the status
00: Timer Unit is 10ms
01: Timer Unit is 1 second
RW
10: Timer Unit is 1 minute
11: reserved
RsvdP Reserved
The number of time units for the watchdog timer.
RW
Write the same non-zero value twice to enable the timer; otherwise the timer is
disabled.
MSM-LP / Special Features
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